The prostomium is rounded or pointed,
and only in species of Lysarete and Kuwaita does it bear small
antennae. Small nuchal papillae are present or absent. The
peristomium consists of two rings and lacks peristomial cirri.
Parapodia are uniramous (neuropodia only) to
sub-biramous where the notopodium is reduced and is only
represented by conical knobs with internal aciculae, or
flattened dorsal cirri. Branchiae are generally absent. The
neuropodia have simple limbate chaetae and
usually simple and/or compound hooks.
Compound spinigers are rarely present (Lumbricalus).
Pectinate chaetae and subacicular hooks are absent. Ventral
cirri are generally absent and pygidial cirri number two or
four. The jaws consist of ventral, fused mandibles and dorsal
maxillae. In most lumbrinerids the maxillae
are of the labidognath type. Some, however, appear to be
transitional to the prionognath type and have been referred to
as sub-prionognath. The maxillae are
mineralised with calcite, and composed of four or five pairs of
symmetrical plates (maxilla I with lateral support or bridle)
and a pair of usually short carriers.
The above description is taken from Paxton (2000), which in turn is based on Fauchald & Rouse (1997).
Identification tips
Recognising the family
Lumbrinerids have compact bodies without prostomial appendages and with small parapodial lobes; often the epithelium is irridescent.
The superficial similarity between lumbrinerids and the Capitellidae sometimes confuses inexperienced sorters, even though these families are not closely related. Lumbrinerids do not have distinct thoracic and abdominal sections which are evident in capitellids. Lumbrineridae also have complex jaws which can often be seen through the body wall and are absent in capitellids. The chaetae of the two families are also very different.
Distinguishing species
Lumbrinerid species are not easy to distinguish, and accurate identifications depend on descriptions of jaws, parapodia, aciculae and chaetae chaetae and their distribution along the body. Proportions of the prostomium and colour patterns may assist initial discrimination of lumbrinerid species.
Several species of Lumbrinerids have been assigned wide geographical ranges, such species probably represent species complexes. An example of one is "Lumbrineris latreilli".
